Fountain pen



L. A. PAUL FOUNTAIN PEN Jan. Wy 1950 Filed April 8, 1947 INVENTOR.

Patented Jan. 17, 195:0

FOUNTAIN PEN Lewis A. Paul, Wichita, Kans., assignor to Beech Aircraft Corporation,Wichita, Kans., a corporation of Delaware Application April s, 1947, serial No. 740,055

2 Claims.

The invention here disclosed relates to writing Y and drawing instruments of the fountain pen type.

Special objects of the invention are to provide a drawing instrument of the reservoir type which may be used in the manner of a ruling pen to lay down accurate lines of constant density.

Particularly important objects of the invention are to enable rapid, continuous drawing of lines of greater length than possible with pens of conventional design and with thick, rapidly drying ink; which will dry immediately and thus not smear or spread upon contact by straight edges or other implements employed in describing such long lines.

Other, related important objects of the invention are to enable the drawing on Various materials other than paper, for example on such materials as metals, plastics and linen, and to provide for the purpose a capillary form of drawing or writing tube terminating in a curved annular bearing edge to form continuous, uninterrupted lines of uniform width and density.

Other important objects of the invention are to provide a pen structure which will be readily adaptable to various writing and drawing purposes, to enable it to be used as desired for general writing, art work, engineering drawings and the like, and with different kind of inks as may be required for such special purposes.

Further objects are to provide a pen such as indicated which by simple handling technique may be used to lay down lines of constant width and which will operate smoothly and uniformly in such adjustments and without scratching or cutting the writing surface in any of its various writing or drawing positions.

Important objects are to provide 'an instrument of the fountain pen type which may be quickly and easily filled or emptied, and without requiring accessory lling devices or the like.

Objects of the invention also are to provide an instrument of the character indicated which will consist of but few, simple parts, be of sturdy, reliable construction, which can be produced at a reasonable cost and which will be generally practical and eicient.

Other desirable objects and the novel features through which the purposes of the invention are attained are set forth or will become apparent in thev course of the following specification.

The drawing accompanying and forming part of the specification illustrates a present commercial embodiment of the invention. Structure, however, may be modified and changed as regards the immediate illustration, all within the true intent and broad scope of the invention as hereinafter defined and claimed.

Fig. 1 in the drawing is a longitudinal sectional View of the pen 2 is a side elevation with the sleeve at the upper or outer end of the barrel appearing broken away and in section to disclose the bearing in which the end cap is rotatably confined;

Figs. 3, 4 and 5 are enlarged cross sectional views on substantially the planes of lines 3 3, ll-ll and 5-5 lof Fig, l;

Figs. 6 and 7 are further enlarged broken sectional details showing different forms of capillary now writing points.

The barrel providing the ink reservoir and handle or grip portion of the pen is shown in Fig. l as made up of an inner cylindrical member I0 and a surrounding sleeve il pressed or otherwise secured over annular supporting shoulders l2, I3, at opposite ends of the cylinder.

The lower end of the cylinder is shown as having a reduced screw threaded tubular projection Ill and a further reduced, smooth finished tubular extension l5, these having a gravity flow passage I6 therethrough serving for both filling and feeding purposes.

RemovalolyV engaged over the end of the barrel there is shown a ferrule or end piece il carrying a projecting capillary flow tube i8 terminating as a Writing point. The removable end ferrule il is shown as having a screw socket I9 in the base portion of the same and a reduced cylindrical extension socket 2li to receive the tube l5.

The capillary flow tube I3 may thus be placed in communication with the feed passage I6 by the simple act of screwing the ferrule Il in place over the end of the barrel. Conversely the feed tube l5 projecting from the end of the barrel may be exposed for filling purposes simply by unscrewing and removing the end piece Il.

The opposite, upper end of the barrel cylinder is shown as externally screw threaded at 2| to receive the correspondingly screw threaded end of a mounting and supporting sleeve 22 for the end or cap structure 23.

The latter is shown as rotatably conned in the mounting sleeve 22 by having a reduced cylindrical extension portion 243 rotatably seated in the cylindrical bearing portion 25 of the sleeve and engaged by balls 26 turning in the annularly grooved portion 2l and held by plugs 28 in radial seats 29 in the mounting sleeve.

The rotatable adjustment of the end cap is for 3 the purpose of effecting longitudinal adjustment of a plunger and piston forming element in the barrel.

This plunger is designated 30 and is shown as carrying a rubber or other suitable packing ring 3 I operating as a piston in the barrel.

To hold the plunger against rotation, the sleeve 22 which is screwed fast or otherwise secured to form the upper end portion of the barrel, is shown as carrying a cross pin 32 extending through a longitudinal slot 33 formed in the plunger.

Longitudinal motion is imparted to the plunger from the cap through the agency of internal screw threads 3d on the inside of the. cap in engagement with the correspondingly screw threaded upper, outer end portion 35 of the plunger.

The plunger carrying the close fitting piston ring or head cam, by the construction described, be longitudinally shifted in opposite directions in the barrel by simply rotating the cap. one way or the other.

By turning the end cap 23 in one direction the plunger may be thrust inward or downward in the barrel to put pressure on the writing or drawing fluid the ink as it may be termed--tol force flow through the capillary tube, as for breaking the surface tension to initiate the capillary line laying action. Such pressure may be utilized to clear any ink material that may have dried at the end of the point after a long period of non-use.

The pen can be quickly emptied at any time by simply removing the capillary end piece I1 and turning the cap 23 to lower the piston 3| in the barrel. The flow passage i6 is of large enough diameter to freely pass the ink both for filling and discharge purposes under impulse of the piston operated by the screw cap 23.

The filling of the pen is quickly accomplished, when the capillary point is removed, by simply dipping the feed tube i5 in the ink supply and rotating the cap 23 to draw the plunger and piston element 35i, 3|, upward in the barrel, the feed passage lE being large enough to serve as a filling passage capable of admitting the ink as fast as the plunger can be retracted.

Capillary tubes of different diameters, lengths and other characteristics, may be quickly interchanged on the same pen body by simply removing and replacing different ferrules carrying capillary ow tubes of the desired or required characteristics.

To enable the capillary pen point to lay down smooth, continuous lines of uniform width and density, the tip of the capillary tube isr preferably formed as illustrated in Figs. 6 and 7, with rounded end surfaces 36, 31, constituting in each case an annular bearing edge of semi-toroidal cross section. In these views the lines 38, 39, represent the transverse planes on which said toroidal formations are based.

These annular bearing edges of toroidal derivation present smooth surfaces to the paper, plastic or other writing or drawing surface, regardless of the angle of inclination at which the instrument is held, and assure uniform continuity of line flow and freedom from scratching or marring the surface operated, on.

The controlledcapillary flow effected through useY of the plungerfenables.,usefof writing and drawing fluids of high' viscosity, quick and substantially instantaneous drying qualities, and this in turn assures that the lines can be kept uniform and of constant density and will dry as applied so that accidental shifting of a ruler, straight edge or other implement used with the pen will not blur or smear the lines.

The use of these quick drying lacquer inks is advantageous further in providing permanent lines which require n0 protective covering and can be washed and cleaned after soiling and which, if corrections are required, can be removed with an ordinary eraser, without scratching,

scurlg or scarring the drawing surface.

The writing or drawing surface preferably is substantially semi-circular in cross section, as indicated bythe radius line 40a, Fig. '7, the contour being governed chiefly by the inside radius at 40. This inside radius may be approximately onequarter the thickness of the side wall of the capillary tube. The taper en the outside need not necessarily be an arc on a radius; it may be an elliptical curve as shown in Fig. 6 or even an approximately straight line.

The feed passage I6 is referred to herein as a gravity flow passage as a matter of indicating its size, it being large enough to permit liquid flow under the force of gravity, as distinct from the capillary ilow controlled by the Writing and drawing point i8. The pen, therefore, may operate at different times under either gravity, force feed or capillary feed, or various combinations. of the three.

What is claimed is:

1. A capillary pen comprising an ink barrel and a capillary tubular writing point mounted on the end of said barrel in communication with the interior of the barrel and having an exposed capillary annular bearing edge of substantially semitoroidal cross section for laying a capillary flow line of ink on a surface engaged thereby.

2. A capillary fountain pen fordrawing longer linesthan possible with a pen of conventional design and forv operating with a thick, rapidly drying ink, comprising an ink barrel, a capillary tubillar writing point mounted on, thel end of said barrel in communication with the interior ofthe barreland having an exposed capillary annular bearing edge of substantially semi-toroidal cross section for laying a capillary flow line of ink on a surface engaged thereby, and a plunger operable in said barrel for applying pressure on, thick, rapidly drying ink contained in the barrel and controlledV as to flow by said substantially semitoroidal, cross sectional, capillary annular bearing edge.

LEWIS A. PAUL.

REFERENCES CITED The following references are of record in the le of this patent: f

Great Britain ISQB 

